History has a way of forcing nations to deal with things left unfinished. Last week’s air strikes against al-Qaeda outposts in Somalia and President Bush’s announcement that he plans to send an extra 21,000 troops into Baghdad are just the latest examples of US foreign policy coming full circle.

Somalia, after all, is where Bush’s father sent 28,000 US troops on a mission of mercy in December 1992. “We come only to feed the starving,” the elder Bush promised. But by 1993, the US and UN had expanded what was a limited humanitarian mission into an overly ambitious reconstruction of Somalia’s government. Tribal leader Farah Aidid soon rallied thousands of Somalis against the nation-building mission. Pitched battles between Aidid’s clan and UN troops ensued, prompting President Clinton to send US Army Rangers and the Delta Force into Somalia to apprehend the warlord.

The US operation culminated on October 3, 1993, in a daylong gun battle in the dusty alleys of Mogadishu. When the guns fell silent, 18 Americans were dead, triggering the beginning of the end of American involvement in Somalia. We didn’t learn until later that bin Laden’s network had provided training to Somali militiamen.

Fast forward 13 years, and Somalia is still a frontline state in the war on terror. Up until a couple weeks ago, when an Ethiopian force crossed the border (doubtless, with the quiet backing of US assets), Somalia was officially under the control of a movement aligned with al Qaeda. In fact, it was Fazul Abdullah Mohammed, the chief planner of al-Qaeda’s 1998 embassy bombings, that US AC-130 gunships targeted in southern Somalia last week. It’s still unclear if they hit their target and sent Fazul to wherever mass-murderers go after they meet their Maker.

Speaking of mass-murderers, Saddam Hussein’s execution has done little to quell Iraq’s postwar war—hence President Bush’s plan to increase troop levels in Iraq and refocus the mission on pacifying Baghdad and its environs. To extend the full-circle metaphor, the President’s plan is an example of a second revolution around the circle.

First, it pays to recall that thoughtful observers warned that the force needed to take down Saddam’s regime was not sufficient to stabilize Iraq, let alone build up a successor government. And so, almost four years after the liberation, the US presence in Iraq is deepening rather than ebbing. Of course, if Senator Edward Kennedy has his way, and US troops are withdrawn from a free but fractured Iraq, they will have to return yet again to restart this painful process and rebuild US credibility. If the senator thinks Iraq is a disaster now, quitting Iraq promises to be worse. Imagine Iraq spawning a Balkan-style ethno-religious war, while serving as a Taliban-style haven for terror. As to the consequences for US credibility, imagine the fall of Saigon, Desert One, and the Beirut and Mogadishu pullouts all rolled into one giant propaganda victory for the enemy.

Second, in a more tragic sense, it pays to recall that thoughtful observers warned that leaving Saddam Hussein in power in 1991 would only defer the inevitable reckoning to some later date. With 500,000 personnel deployed and a large swath of Iraq occupied, the US had all the troops and logistics lines it needed to overthrow Saddam’s regime and occupy postwar Iraq in February 1991, when Washington declared its preemptive ceasefire.

To be sure, there would have been more American casualties had Gen. Schwarzkopf’s juggernaut marched to Baghdad, but would the number of dead have eclipsed 3,000?

There also would have been some agitated neighbors, but they would be no more agitated than they are today. In fact, Turgut Ozal’s Turkey was far more cooperative than the Turkey of today. The Iran of 1991 was far weaker than Ahmadinejad’s Iran. And internally, the US would have found far more support from an Iraqi populace unscathed by the cold calculations that marked the end of Operation Desert Storm—the calculations that allowed Saddam to take out his postwar rage against thousands of his subjects in northern and southern Iraq.

Brent Scowcroft, James Baker and other realists point to today’s Iraq to justify those calculations. “The United States could conceivably still be an occupying power in a bitterly hostile land,” Scowcroft and the elder Bush concluded in A World Transformed. Of course, that’s effectively what happened, at least in the eyes of bin Laden and his followers. In a sense, occupation was inevitable after the war; perhaps the United States ended up occupying the wrong country. Since a wounded Saddam could not be left unattended and an oil-rich Saudi Arabia could not be left unprotected, US troops took up permanent residence in the Saudi kingdom. The presence of foreign troops in the Muslim holy land galvanized al Qaeda, which carried out the attacks of September 11, which triggered America’s global war on terror, which led inevitably back to Iraq, which is where America finds itself today. And now the circle is complete.

This unfinished business from yesterday begs a sobering question: What other foreign policy failures have yet to come full circle? In 1979, Iranian radicals stormed the US embassy in Tehran and held America hostage for 444 days. The most Washington could muster was an abortive rescue mission that ended in the same way the entire ordeal began—in humiliation. A few years later, Hezbollah killed 241 Marines trying to keep the peace in Beirut. Foreshadowing the Mogadishu misjudgments, Washington’s response was a few volleys from the USS New Jersey and a rapid retreat.

With Iran and its Hezbollah henchmen now in ascent, history has much more unfinished business for America to address.